Fertility awareness can help orthodox or observant Jewish couples fulfill their religious obligation to bear children while adhering to Jewish law, which prohibits intercourse during any uterine bleeding. Knowing when you are most fertile is useful whether you are trying to get pregnant or space your pregnancies.
Jewish Laws and Fertility Awareness
Some women who observe Jewish law (halacha) might go past their fertile days before they can resume sex each menstrual cycle. You may have difficulty timing intercourse to conceive when observance of the halacha of niddah prohibits sex or other physical contact with your husband during menstruation plus seven more days.
As an orthodox or observant Jewish woman, fertility awareness used for natural family planning worldwide, can help you:
- Identify the fertile days in your cycle to increase your chance of getting pregnant
- Fulfill your husband's and your halachic duty to procreate
- Space your pregnancies if necessary and permitted
You should have intercourse at least every other day during the days you identify as fertile. If you are not planning to conceive that cycle, delay intercourse until your infertile days, or use temporary birth control during your fertile days if that is the recommendation or your preference
Fertility Awareness Methods
Fertility awareness methods that orthodox and observant Jewish women can use track one or more of the natural signs of fertility. Signs include changes in your cervical mucus, the position of your cervix, and your basal body temperature. The methods integrate knowledge about the:
- Hormonal events of the normal menstrual cycle and the timing of ovulation
- Lifespan of the egg, which survives only for about 12 to 24 hours and may be nonviable if niddah ends 24 hours or more after ovulation
- Lifespan of the sperm, which can live for 72 hours or more. There may be viable sperm still present if you can have sex only once after niddah and don't ovulate until three days or more later.
Knowledge of the lifespan of the egg and sperm helps you understand how the timing of intercourse increases your chance of pregnancy during your fertile days.
The Cervical Mucus Method
With the cervical mucus fertility awareness method, you observe your vaginal secretions daily after your period ends to identify your most fertile days. The important points to understand about this method are:
- You are most fertile on the days you notice secretions on your underwear or feel wet.
- To increase your chance of getting pregnant, have intercourse from the day you see or feel mucus.
- Rising estrogen level increases your cervical mucus and makes it thinner, more watery, and more stretchy. These properties are greatest a day or two before ovulation.
- The day after ovulation, your mucus decreases in quantity and gets thick, cloudy, and tacky because of progesterone.
- Douching, vaginal infection, medications, and intercourse will make it harder to interpret your secretions.
A study in Family Planning Perspectives in 1990 reported a 3.1 percent pregnancy rate if this method is used perfectly for birth control, meaning there is no sex on fertile days. This means the method identifies the optimum days of fertility 96.5 percent of the time if you are trying to get pregnant or avoid conceiving.
The TwoDay Method
The TwoDay fertility awareness method is based on daily observations for the presence or absence of cervical mucus:
- If you notice or feel secretions today, you ask yourself, "Did I have secretions yesterday?"
- You are fertile from the time you notice secretions on your underwear or feel wet two days in a row until you have no secretions.
Based on results of a study published in Fertility and Sterility in 2004, the TwoDay method identified the best days of fertility 96 percent of the time.
The Standard Days Method
The Standard Days method is a calendar-based fertility awareness method based on menstrual cycle lengths. According to a 2006 Journal of Midwifery Women's Health article, the Standards Days method works best if your cycles are 26 to 32 days long. Based on this, the standard days are set as:
- Days 8 to 19 are fertile days when you are most likely to get pregnant.
- Days 1 to 7 and days 20 up to next period are infertile days, and you are unlikely to get pregnant.
A study published in 2002 in Contraception reported a pregnancy rate of 4.8 percent when there is no sex on fertile days. This translates to 95 percent effectiveness of marking the best days to get pregnant with this method.
The Basal Body Temperature Method
The basal body temperature (BBT) method tracks your temperature from the first day of a period to first day of the next, which defines one menstrual cycle. Important points of this method include:
- You take your temperature first thing in the morning before getting out of bed, moving around, eating, or drinking
- Your BBT stays below 98 degrees Fahrenheit before ovulation.
- BBT rises above 98 degrees a day after ovulation because of increased progesterone.
- Your temperature stays up until the day your next period starts, about 12 to 14 days after you ovulate. You are most fertile two to three days before this shift in your BBT.
Note the BBT method is not useful for identifying your fertile days during a current cycle. However, it helps you predict which day you will likely ovulate in the following cycles if they are regular. This can help you validate the timing of other fertility signs in relation to ovulation.
The Symptothermal Method
The symptothermal method combines the BBT and the cervical mucus methods as one family planning practice. Combining two methods increases the accuracy in identifying your fertile days. Or, you can combine your BBT with the Standard Days or the TwoDay methods.
A study on the BBT plus cervical mucus methods published in Human Reproduction in 2007 reports a 0.6 percent pregnancy rate with perfect use of this method. This means it is 99.4 percent effective in identifying the days of increased fertility.
The Fertile Days and Niddah
Consider the following if your niddah status encroaches on your best days of fertility, and you are trying to get pregnant:
- If your cycles are the average 28 days long, days 12 to 14 are your most fertile days - the days you will likely ovulate.
- However, you are fertile for six days, based on a National Institutes of Health study published in 1994 in the New England Journal of Medicine.
- Your increased fertility for the six days starts five days before ovulation and is maximum on the day of ovulation.
- Twenty-four hours after ovulation, you have little chance of conceiving because the egg is no longer viable.
If you have 28-day cycles and observe the minimum of 12 days of niddah, you will be near or at ovulation when you can take your ritual immersion bath (the mikveh) and resume intercourse. This is great timing when you are trying to get pregnant. However, when your cycles are shorter or your period lasts more than five days, you may have ovulated already, and this will be a problem if you are trying to get pregnant.
Because orthodox Jewish views on fertility is guided by the halachic obligation (the great mitzvah) to "be fruitful and multiply" (pru urvu), according to the Chabad website, infertility can cause great anguish. Your devotion to halacha might make you believe you are infertile when instead you might be missing your fertile window each cycle because of niddah.
Tracking your fertility signs can provide evidence of this if you have to seek guidance from your rabbi. He may allow an exemption (a heter) to shorten your niddah to improve your chance of pregnancy, according to an article in Jewish Women's Health on infertility and Jewish law.
If you are diagnosed with true infertility and choose not to adopt children, you are permitted to use various types of infertility treatments. According to Nishmat's Women's Health and Halacha, allowed fertility treatments include:
- Ovulation medications, such as clomiphene citrate
- Artificial insemination with husband's sperm, including intrauterine
- In vitro fertilization
- Infertility surgery
Consult with your rabbi to ensure a treatment is approved and that appropriate halachic supervision will avoid or minimize breaking a law. According to the Chabad review, note that:
- Fertility specialists have to be made aware of the Jewish law that prohibits a man from spilling or wasting his sperm in vain (zera levatala) during an infertility procedure.
- A Jewish women can only be inseminated with sperm from her husband.
- Use of donor egg is controversial because there would a question of who the mother is according to Jewish laws on matrilineal descent.
Fertility Awareness and Contraception
If you must avoid or delay pregnancy, use fertility awareness to help you plan when to delay intercourse after niddah or use birth control. An article in My Jewish Learning notes that, in general, Jewish law allows women to use contraceptives, especially if getting pregnant is risky to your health or life. When permitted to use a contraceptive, some Jewish women may use fertility awareness to help them limit its use to the most fertile days of the cycle instead of using a daily method.
Choices of Contraceptives
If you must or choose to use birth control to avoid or space pregnancy, Rabbinic scholars appear to favor the birth control pill, according to the My Jewish Learning article, although it can cause breakthrough bleeding. Other allowed hormonal contraceptives, such as the vaginal ring and injectable hormones can also cause irregular bleeding, prolong niddah status, and interfere with sexual relations.
Temporary birth control methods allowed include vaginal spermicides and the diaphragm, which is controversial in Jewish law because it interferes with intercourse. A man cannot use a condom or withdraw during intercourse as a form of birth control. These methods are against the law against wasting sperm in vain.
Easy Family Planning
Women worldwide use fertility awareness as an easy, natural family planning method to avoid pregnancy. Orthodox and observant Jewish couples can use these methods to help them integrate their halachic obligation to have children, their plans for family spacing, and a commitment to niddah.