Around the world, hormonal contraceptives come in a variety of forms: pills, injections, patches, and vaginal rings. The most common types of hormonal contraceptive combine synthetic versions of two hormones: estrogen and progesterone. These hormones prevent ovulation, making conception impossible. (Progesterone-only pills, also known as the mini-pill, work differently. Please see here for a more detailed discussion.)
This method is about 99% effective with perfect use, and about 92% effective with typical use.
Combined hormonal contraceptives are most commonly prescribed on a 28-day cycle: 21 days of hormones, followed by seven days of a placebo or break. Withdrawal bleeding (often similar to a light period) generally begins about 2-4 days after stopping the hormones each cycle.
The 28-day cycle, although convenient for medical calculations, is simply a matter of convention. When medically acceptable, a woman can adjust or lengthen her cycle with many varieties of hormonal contraception. Still, most contraceptive formulations must be interrupted periodically to allow for shedding of the uterine lining, and any alteration in timing should be discussed with a health care professional. Please see here for a more detailed discussion.
There are many different types of pills, which vary based on their estrogen dosage and on the formulation of synthetic hormones that they contain. With some formulations, all the active pills are identical. With others, the dosages of estrogen and progesterone fluctuate over the course of the cycle.
Pills also vary based on the schedule on which they are meant to be taken. Some pills are packaged to be taken for three months consecutively, followed by a week of a placebo or a lower dose of estrogen during which a woman is likely to experience withdrawal bleeding. Other pills are taken continuously without any break, and without defined episodes of withdrawal bleeding.
The adhesive patch releases hormones that are absorbed through the skin. A woman typically wears a patch for three consecutive weeks (changing patches weekly), followed by a patch-free week.
The ring is made of flexible plastic, and inserted into the vagina for three weeks, releasing hormones for absorption through the vaginal lining, followed by a ring-free week.
As noted above, a health care provider may suggest extending the number of weeks using the patch or ring.
In some countries (not including the US or Israel), combined hormonal contraceptives are available as a monthly injection.
A woman should consult her physician about any side effects that trouble her. In some cases, it is best to wait and see if the body adjusts to the current formulation; in others, it is worth trying a new formulation or a new method altogether.
Intermenstrual (“breakthrough”) bleeding is common during the first few cycles of hormonal contraception, as the body adjusts to the new hormonal milieu. This usually subsides after two or three cycles. If intermenstrual bleeding does not abate after three cycles, a woman should consult her physician, keeping in mind that switching to a new formulation can mean starting the adjustment process all over again.
In general, the lower the dose of estrogen, the higher the likelihood of intermenstrual “breakthrough” bleeding. The likelihood of intermenstrual bleeding and its potential halachic effects (see below) should therefore be taken into account by a physician when determining which version of hormonal contraception to prescribe.
Hormonal contraceptives are also sometimes associated with various other side effects, including changes in mood, and a decrease in sexual desire for some women.
Combined hormonal contraceptives can sometimes reduce breastmilk supply. Therefore, progesterone-only formulations are usually prescribed for nursing women. However, combined hormones are safe for use during breastfeeding, and can be used as necessary.
If breastfeeding has been well established, a woman beginning combined hormonal contraceptives may be able to preserve her milk supply by increasing both the length and frequency of feedings. If the baby is old enough (over six months), increasing solid foods can also help compensate for any decrease in breastmilk.
Estrogen can increase the risk of blood clots, although this risk remains very low for most women – and significantly lower than the risk of blood clots during pregnancy. Smoking, high blood pressure, a personal or family history of clotting, or a significant history of migraines, can indicate an increased risk, and may be a reason not to use this method.
A follow-up exam to check blood pressure is recommended a month or two after starting.
There is some medical disagreement about the link between hormonal contraception and cancer: it may increase the risk of some cancers but decrease the risk of others.
For these reasons, it is important for these medications to be prescribed only by licensed health care providers, after taking a careful personal and family health history.
Hormonal contraception is considered a halachically permissible method when contraception is allowed, and has a number of halachic advantages: Its effect is temporary and reversible, it does not destroy sperm, and it does not interfere in any way with the normal course of marital relations.
This method also has the advantage of enabling a woman to regulate her cycle to become niddah less frequently or to avoid being niddah at inconvenient times. When medically acceptable, manipulating the cycle presents no halachic problem, because a woman is not halachically required to become niddah monthly (or ever).
On the other hand, hormonal contraception is associated with intermenstrual bleeding, which can raise halachic questions, the ring affects bedikot, and the ring and patch are considered chatzitzot. (See below.)
Intermenstrual (“breakthrough”) bleeding is assessed based on the usual laws of stains. It can, but will not necessarily, make a woman niddah. It’s a good idea to review the halachot of stains before starting on a hormonal contraceptive, and to be careful with precautions such as colored underwear and waiting before wiping.
Dealing with unexpected bleeding while trying to complete the clean days can be more complicated. A woman who is having trouble reaching the mikveh should consult individually with a halachic authority.
Most women have some bleeding each cycle after stopping active pills or removing the patch or ring. This bleeding is medically considered withdrawl bleeding rather than menstruation. Nevertheless, it is uterine, and thus can make a woman niddah.
Some women experience only very light withdrawal bleeding while using hormonal contraception. Bleeding that is lighter than a light period is evaluated based on the usual criteria for staining, described in our articles on stains and toilet paper. A woman can take precautions to avoid becoming niddah from staining (e.g., wearing colored underwear, waiting before wiping after urination). It is recommended – but not halachically required – to abstain from relations during staining as a precaution against finding blood immediately after relations.
Even if staining occurs regularly every cycle after stopping the hormones, it is not automatically considered a “period” that makes a woman niddah. Here, too, the staining should be assessed based on the usual laws of stains.
Contemporary rabbinic authorities differ about the effect of the artificial cycle produced by the hormones on the calculation of vesatot. Please see here for a more detailed discussion.
Bedikot with the Ring
A woman should remove the vaginal ring for the hefsek taharah to ensure that she can do a thorough bedikah of all folds and recesses. Ideally, she should also remove it for one bedikah on day one of the shivah neki’im, and one bedikah on day seven.
Since the ring is thin, flexible, and movable, a woman can just push it aside when performing the other bedikot. If she finds removing the ring uncomfortable or if she suspects that removing it will cause an abrasion, she should ask a specific halachic question.
A woman should remove the ring before mikveh. However, if she forgot to do so, her immersion remains valid.
The patch is considered a chatzitzah and a woman needs to remove it before mikveh, along with all adhesive. If she forgot to do so, she needs to immerse again. If she realizes only the next morning, she should ask a specific halachic question.
According to the package inserts, removing the NuvaRing for less than three hours, or the ORTHO EVRA patch for less than 24 hours, does not impair their contraceptive effect.
According to the ORTHO EVRA package insert, a woman can put the original patch back on after immersion if it is clean and still sticky. Otherwise, she should use a new patch.
Updated October 2021