Between old wives’ tales about sex positions and TikToks about eating pineapple, it can be hard to separate science from ideas that border on science-fiction when it comes to trying to conceive. We rounded up some of the Clue community’s most-asked questions and sat down with our resident fertility nurse and Clue science writer, Eve Lepage, to get all the answers:
Is it true that your fertility ‘falls off a cliff’ after 35?
Yes, and no – definitely no cliff involved. It’s true that there is a slow decline in the rates of first-time pregnancies that begins in the late 20s and continues into the mid to late 30s (1,2). But the idea that everything is optimum before age 35, and then fertility drastically nose-dives after 35 is misleading. It is important to know that your ovaries don’t always age at the same rate as your chronological age. It’s possible to experience challenges conceiving on either side of 35.
The likelihood of conception is based on the individual, and it may still be possible to conceive well into your 40s, but the chances of taking home an infant are lower (3). Pregnancy later in life can have a higher risk of complications for both the birthing person and the fetus/newborn, so getting early and regular prenatal care is important (3). If you’re 35 or over, it’s recommended that you seek medical advice if you’ve been trying to conceive for more than six months, or right away if you are 40 or over (4,5). And of course, age isn’t the only factor to consider, your medical history and lifestyle play a role, too (5).
Do sex positions matter when it comes to trying to conceive?
While that’s a popular myth across many cultures, no particular sex position has been proven to improve the chances of conceiving. Sperm arrives at the cervix within seconds of ejaculation, no matter which position you’re in (5,6). And within 2 to 10 minutes, sperm can be found in the fallopian tubes, where fertilization (sperm meeting egg) can occur (7,8). The most important thing is to find a position that is comfortable and feels good for you and your partner. Conceiving can take some time, so you might as well enjoy the experience.
Does holding up your legs and hips after sex increase the odds of getting pregnant?
No, your position after sex doesn’t matter either. There’s no scientific evidence that elevating your hips or lying down after sex helps sperm reach the cervix (5). The sperm swim towards the egg, so getting up doesn’t cause them to “fall out” (9). A European study of nearly 500 intrauterine insemination (IUI) patients found that those who remained lying down for 15 minutes after the procedure had no difference in pregnancy rates compared to those who got up immediately after (10). But old habits die hard, and fertility clinics still tend to have patients remain lying down for 10-15 minutes after IUI. So if you want to do this at home too, go ahead.
Is it true that if you're trying to get pregnant your partner shouldn't masturbate or you should limit sex outside of your fertile window to increase the sperm concentration when you do try?
There isn’t much evidence to suggest that ‘storing up’ sperm outside of the fertile window has any benefit, and it could actually negatively affect sperm quality if it’s been longer than 5–7 days since ejaculating. In fact, the World Health Organization (WHO) recommends a period of abstinence (no release of sperm) of a minimum of 2 days and a maximum of 7 days when providing a sperm sample for fertility treatment (11). But research suggests that a shorter abstinence may lead to better sperm quality, and the European Society of Human Reproduction and Embryology (ESHRE) recommends just 3–4 days of abstinence (12). The bottom line: Aiming to have sex or inseminate every 1–2 days during the fertile window can increase the odds of conceiving (5).
When a transgender/transmasculine person has taken testosterone, does this completely rule out the chances of conceiving a child?
Not necessarily. Masculinizing testosterone hormonal therapy generally has a negative impact on fertility (read more about it here) as it usually prevents ovulation from happening (13). But many people have been able to become pregnant either naturally or through in vitro fertilization (IVF) after stopping testosterone (14,15). However, little is known about the long-term impact of testosterone therapy on ovarian function, so it’s often recommended to freeze eggs prior to starting gender-affirming treatment, if you think you might want biological children in the future (13,16,17).
Can eating certain foods influence the sex of your baby?
No. The sex of a baby is determined at conception; the sperm carries the genetic material that decides the genetic sex, and there is no way to control which sperm will successfully meet the egg (9). So, there is nothing you can do to increase the chances of having a boy or a girl. The only exception to this is if you’re doing IVF, then in some cases sex selection of an embryo is possible, although usually only for medical reasons (18).
Some people recommend eating pineapple to increase your chances of conceiving. Is there any science to back that up?
The concept of eating pineapple to increase your chances of conceiving has to do with a group of enzymes called bromelain found naturally in pineapple (19). Some studies have shown that bromelain might help decrease inflammation – and inflammation might make it more difficult to become pregnant (20) – but this hasn’t been studied in humans (21). Bromelain is also thought to have anticoagulant properties – meaning it can reduce the chances of blood clots and potentially increase blood flow to the uterus – but again, research is limited and this hasn’t been studied in humans (22).
Some people say that these anti-inflammatory and anticoagulant properties can increase the chances of an embryo implanting into the uterus, but there aren’t any studies to back up these claims. It’s unlikely that eating pineapple or supplementing with bromelain has any effect on implantation. But there are benefits to eating pineapple; it’s high in vitamin C and other nutrients, so adding it to your diet in moderation isn’t a bad idea (23).
If my mother struggled with fertility issues, does that mean I will too?
It’s possible. Some medical conditions that can affect fertility like polycystic ovary syndrome (PCOS), endometriosis, fibroids, and thyroid disorders may have a genetic component (24-27). That means it’s possible for the condition to be passed down through generations. Likewise, some genetic conditions like Turner syndrome and Fragile X syndrome can increase the risk of primary ovarian insufficiency (28). This is the clinical term for when the ovaries do not produce as many follicles as is typical in a person who is under 40 (29).
So if you have a family history of fertility challenges, or early menopause, it’s important to speak to a doctor before trying to conceive so they can run some tests and discuss a plan with you. This is one of the reasons why scheduling a preconception visit with an OB/GYN or midwife before trying to become pregnant is so important (30).
Does having an irregular period mean you’re less likely to conceive?
Yes, it can be more difficult to become pregnant if you experience “irregular cycles”, the term healthcare providers use to describe menstrual cycles that vary by more than 7–9 days in length (31). If your cycles are unpredictable, you might not ovulate (release an egg from the ovary) regularly (31). This can make it challenging to predict ovulation and to plan sex or insemination during the fertile window, since the timing can change significantly month-to-month (32). Unpredictable cycles can also be a sign of an underlying medical condition like PCOS or a thyroid disorder, so it’s important to speak with your healthcare provider about your cycle characteristics whether you’re planning to become pregnant or not (33,34).
Does a female orgasm during sex help improve chances of conception?
Unlikely. It’s been theorized that contractions of the uterus that happen with orgasm may help “suck up” semen deposited in the vagina near the cervix. While it’s not conclusive, one study measured the amount of “flowback” (how much semen leaked out of the vagina after sex) and found that sperm retention was greater when orgasm occured (35). But it’s important to understand that having an orgasm hasn’t been proven to increase pregnancy rates themselves, and you certainly don’t need to orgasm to become pregnant (36). Orgasms feel great, though. So, there’s that.
Do alternative medical treatments like acupuncture affect fertility and can they increase your chances of becoming pregnant?
Maybe. Integrative (sometimes called alternative) medicine practitioners around the world have recommended acupuncture for all kinds of medical conditions that affect fertility including PCOS, fibroids, endometriosis, and issues with egg reserve and sperm quality to name a few (37). While some studies have shown acupuncture alongside fertility treatments like IVF can increase the chances of becoming pregnant (38,39); other studies have not (40,41).
If you decide to give acupuncture a try, it’s important that you see a qualified practitioner. In the United States, an acupuncturist should be registered with and accredited by the relevant regulatory bodies (such as NCCAOM or ABMA) (37).
Get Clue Plus to access the new Clue Conceive mode in-app. Clue Conceive provides personalized predictions for fertile days that can help you time sex or home insemination to conceive faster, based on clinically-tested technology.