Frequently Asked Questions

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How do I know when I am fertile?

Your cervical mucus will indicate your fertility by its characteristics and patterns:

  • Following menstruation, a sensation of dryness, with no mucus, indicates infertility.
  • A discharge which continues without change day after day in the early days of each cycle, or for more than two weeks, also indicates infertility.
  • Mucus which differs from either of these patterns suggests an altered level of fertility. If the mucus feels slippery and wet, and perhaps forms clear strings like raw egg-white, you are probably at your most fertile time.

Keeping a daily record will show how the mucus changes from time to time. The pattern is the best way to recognise both fertility and infertility. Every woman’s pattern is a little different, but she quickly learns to recognise it herself.

How do I find the mucus?
The mucus will make its presence felt at the vulva around the vaginal opening. You do not need to touch the vulva or feel inside the vagina: this will merely confuse you because the vagina is always moist. Be alert to the sensations at the vulva and notice any visible mucus in the normal course of caring for your personal hygiene. Tuning in to your fertility will soon become second nature to you. There is no need to touch the vulval area with the fingers, simply be aware of the sensation at the vulva as you are going about your normal daily activities.

How many days in a cycle is the average couple fertile?
The changing, developing pattern of mucus may last 3-5 days until the Peak is recognised. Then you need to wait a further 3 days past the Peak if you do not wish to conceive (see Peak Rule). Scientific studies show that the egg lives for about twelve hours, and sperm can maintain their fertilising capacity for three to five days in the presence of the mucus.

How many days are available for intercourse in a typical 28-day cycle?

Results from a World Health Organisation trial of the Method indicate that about half the days of a 28-day cycle are generally available for intercourse. Days of abstinence include the menstrual period, the time when mucus indicates possible fertility until the Peak is recognised and the three days after the Peak.

The Rules mean what they say – any departure from the guidelines may result in conception.

In short cycles fewer than half the days may be available for intercourse, whilst in long cycles, such as when breastfeeding, considerably more days are available.

You say that sperm can live for up to five days. What if I don’t have five days of fertility to warn me that ovulation is approaching?
Sperm cannot pass through the cervix or maintain their fertilising capacity without mucus, because the vaginal environment is hostile to them. So, if you are fertile for only two days, or even half a day of the cycle, sperm vitality will be reduced correspondingly. However many days you are aware of the mucus, you will always have sufficient warning of the approach of ovulation by the change from your infertile pattern.

Why is it important to make love only at night?

Why is it important to make love only at night in the first part of the cycle before fertility becomes apparent?
You need to be up and moving around for a few hours so that the mucus can flow down from the cervix to the vulva and make itself felt and seen. Intercourse upon waking in the morning would not enable you to be aware if the mucus had started during the night, indicating potential fertility, and so a pregnancy may result. Once you have recognised the Peak, and waited for three days, intercourse is available on any day at any time until the beginning of the following menstruation.

Why do you advise waiting as soon as there is a change from the infertile pattern?

It is impossible to predict in any cycle just when ovulation will occur. As soon as a change from the Basic Infertile Pattern is recognised, you are potentially fertile, because the mucus enables sperm to enter the uterus and maintains sperm vitality for up to five days. The rule to avoid intercourse when fertile signs become apparent ensures that there are no sperm cells present when ovulation occurs.

Can the guidelines be used more flexibly?

Can the guidelines be used more flexibly once a woman has long experience of assessing her own pattern of fertility?
Many women find after using the Method for some time that they can enjoy more freedom for intercourse than the guidelines recommend and still avoid pregnancy. The guidelines have been laid down for maximum security and contain a built-in safety margin. However, couples who adopt a more flexible approach should be prepared for the possibility of a pregnancy.

Can I learn this method from a book?

Many women have successfully taught themselves and manage quite well so long as their cycles follow a familiar pattern. However all women will find at some time or other that their pattern changes, even if only as a result of getting older. Your Billings Ovulation Method® tutor has been thoroughly trained and is required to continuously update her knowledge to maintain accreditation. Therefore she will be able to help you to interpret your pattern, whatever the circumstances, and will assist you to maintain confidence even when the pattern may be somewhat erratic, for example in times of stress or when returning to fertility after breastfeeding.

There are accredited tutors of the Billings Ovulation Method® available in many countries around the world where you can obtain individual, confidential assistance. This is best done face-to-face, but can also be successfully achieved via our telephone counselling service or internet teaching service. Details of your nearest teaching centre are available by contacting us.

Doesn’t this Method take the spontaneity out of love-making?

The use of any natural method means that you cannot always have intercourse when you feel like it. To avoid pregnancy you can’t have intercourse when you are fertile. This approach needs to be discussed and mutually agreed upon. Weighed against this are the many days when love-making can be completely spontaneous, free from drugs or devices and from any doubts about the side effects of contraceptives, including the lowering of libido.

Will I be able to detect changes in sensation?

I can recognise changes in the appearance of my mucus, but will I be able to detect changes in sensation?
Our experience is that the vast majority of women can learn to detect the sometimes subtle changes in sensation, in fact studies show that most women can produce a chart of a recognisable mucus pattern after only one month of learning the Billings Ovulation Method®. Sometimes, paying too much attention to the appearance of the mucus can cause confusion. Then your Billings Ovulation Method® tutor may suggest you “chart blind” for one cycle. This almost invariably results in a more accurate chart.

Does stress affect the mucus pattern?

Stress due to emotional upset or illness may delay ovulation and lengthen cycles. Regular strenuous exercise, such as an elite athlete in training, may eliminate ovulation and menstruation. In both situations the pattern will regularise when life gets back to normal. There is no evidence to indicate that stress speeds up ovulation.

Can intercourse trigger ovulation?

No. Hormonal studies on humans have shown that there is a complicated and precise physiological process over several days leading up to ovulation. Stress may delay ovulation, but intercourse has never been shown to hasten this process, unlike in some other species.

Can drugs or douches affect the mucus?

Do any drugs affect the mucus?
Yes, indirectly, the following drugs alter the mucus pattern with variable effects in different women:

  • Some tranquillisers, eg Largactil, by causing raised prolactin resulting in delayed ovulation. However, when ovulation does occur it will be recognised by the familiar mucus pattern.
  • Hormones, for example progesterone and oestrogens, by interfering with the woman’s normal hormonal levels will change the mucus pattern.
  • Antihistamines – some women only are affected. Individual charting will soon determine this.
  • Cytotoxic drugs used in the treatment of cancer. These prevent mucus production by a direct action on the ovaries.
  • Antibiotics – women taking antibiotics for a severe illness sometimes notice a change in the mucus pattern. This is an effect induced by the stress of the illness and not the drug. Women on prolonged antibiotic treatment for chronic illness can interpret their mucus pattern successfully.

Do vaginal sprays and douches alter the mucus pattern?
Yes – by producing an artificial wetness which may confuse your interpretations of the mucus. They may also cause an allergic reaction or inflammation, resulting in an infective discharge which alters the mucus pattern.
While cleanliness is essential to good health and an important consideration in a sexual relationship, it is unnecessary and inadvisable to use these preparations to clean the vagina. The vagina is self-cleansing and external washing is quite adequate.

Can I combine condoms or a diaphragm with the method?

No. There is a good biological reason for not using barrier methods during your fertile phase. The seminal fluid and vaginal secretions associated with intercourse will tend to confuse your mucus pattern and will make it more difficult to assess your fertility correctly. All barrier methods have a method failure rate so using them during the fertile time may result in a pregnancy. Only abstinence from genital contact can ensure you will not become pregnant while you are fertile.

Is the amount of mucus important?

I seem to have only a trace of mucus. Is the amount of mucus important?
For conception to occur, it is essential that some mucus is produced because without it sperm cannot survive. Some women find that only after they start paying attention and keeping a daily chart do they realise just how much mucus they are producing. Some women produce very little visible signs of mucus, but they are aware of the change in sensation. This pattern is normal for the individual and she can manage her fertility very well using the Billings Ovulation Method®. If you are completely dry throughout the cycle your fertility may be impaired. This may occur if you have only recently ceased taking chemical contraception, in which case it will likely improve with time and patience. However, if there is no obvious explanation, or if the situation persists, you should consult a doctor.

Can I become pregnant in the 'early' days?

Will I become pregnant if I make love on the first day after noticing a change from my Basic Infertile Pattern?
The change from an infertile pattern indicates an alteration in hormone levels and therefore possible fertility. You thus increase your chances of becoming pregnant if you make love on that day.
Some couples experiment with these early days of potential fertility and find that they do not conceive. But if couples are strongly motivated to avoid a pregnancy, they should avoid intercourse on any day when the mucus pattern indicates possible fertility.

A friend of mine says she conceived after making love during her period. Is this possible?
It is possible to conceive during menstruation, particularly if your cycles are very short. The shorter your cycle the earlier you ovulate. Ovulation will always be preceded by the changing mucus pattern, however if the bleed is sufficient to mask the presence of mucus you would not notice that you are already fertile. This is why the first rule of the Billings Ovulation Method® calls for avoidance of intercourse on days of heavy bleeding during menstruation if the couple wishes to avoid pregnancy.

Is it necessary to maintain abstinence during menstruation if over a long time of charting you have never had a short cycle?
There is no guarantee that your body will always follow the same pattern. For example, often the onset of pre-menopause is marked by shorter cycles when ovulation occurs much earlier in the cycle than was previously the case. If you have intercourse when menstrual bleeding may obscure the mucus you have to accept the possibility of pregnancy.

Can this method help me to get pregnant/choose the sex of my child?

I have been trying to have a baby for more than a year. Can the Billings Ovulation Method® help me to become pregnant?
Charting your cycles according to the Billings Ovulation Method® will greatly enhance your chances of identifying the optimum time for conception in your cycle. It is suggested that you apply the Early Day Rules as normal to enable you to recognise the onset of potential fertility. If you then refrain from intercourse until the sensation is slippery and the vulva may be soft and swollen, you will maximise your chances of conceiving. Intercourse is recommended over the slippery days and for the first couple of days after the Peak. Even if cycles are long and ovulation infrequent, using these guidelines will give you the best chance of achieving your desired pregnancy.

Can the Billings Ovulation Method® be used to choose the sex of my baby?

The scientific evidence on this is controversial, however anecdotal evidence tends to indicate that an act of intercourse early in the development of the characteristic mucus (when the sensation first becomes slippery) is more likely to result in a girl, while an act of intercourse on the Peak day or the day after is more likely to result in a boy. A study in Nigeria appeared to confirm this tendency: success in pre-selection of a boy was achieved by 310 couples, failure in pre-selection of a boy occurred in four couples. Success in pre-selection of a girl was achieved in 90 couples, failure in pre-selection of a girl occurred in two couples.

Pre-determination of the sex of a baby is never likely to be 100 percent reliable.

Is it possible to ovulate twice in a cycle?

Is it possible to ovulate twice in a cycle? Does this affect the reliability of the Method?
It is possible to release two or sometimes more eggs in a cycle, but all the scientific evidence shows this will always occur on the same day, so all aspects of the Billings Ovulation Method® still apply. Sometimes, particularly if you experience sudden stress in the early part of your cycle, you may notice that the mucus pattern begins to develop but does not go on to a Peak, instead it dwindles away and you return to your Basic Infertile Pattern. Then fertility may return, this time proceeding to a Peak and followed as usual by menstruation. In such a case the whole cycle will be longer with two “patches” of mucus, but only one Peak and only one day of ovulation. If a woman is not familiar with the Billings Ovulation Method® she may mistakenly think she has ovulated twice, but this is not so.

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