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Talk to your doctor if you have unexplained vaginal bleeding, amniotic fluid leaking from your vagina, a multiple pregnancy, or a history of preterm labor. Your doctor may also discuss placenta previa with you, which is when the placenta covers the cervical opening. These conditions may make you more prone to complications, and pelvic rest may be recommended. If you have a new partner or are not monogamous, practice safe sex during pregnancy with condoms and dental dams. Bacteria and viral infections from sexually transmitted diseases can affect your pregnancy and growing baby. Avoid lying flat on your back in the second and third trimesters. In this position, your growing uterus puts pressure on a major artery in your body, which may reduce blood flow to your baby and make you feel lightheaded. Instead, try to lie on your left side. Ask your partner not to blow air into your vagina during oral sex. In rare cases, this puff of air can block an artery, potentially harming the baby. Air blocking an artery in this way is called an air embolism. Try other forms of intimacy in the third trimester if your partner has cold sores (HSV1) or genital herpes (HSV2). Herpes can cause neonatal herpes when a mother with no antibodies is infected for the first time in late pregnancy. While herpes is mostly a minor nuisance for adults, it can be fatal in infants. Ask your doctor about oral suppression medication for you and/or your partner. People with oral herpes (cold sores) can transfer the virus to the genitals of a partner during oral sex, particularly if they have an active sore. It's best to avoid performing oral sex on a pregnant mother. If you don't have herpes, be sure to use a condom each time you have sex when you are pregnant. Even if your partner doesn't have symptoms, you could still contract herpes if you don't use protection. Refrain from having sex when your partner has an outbreak at any time during your pregnancy. If you and your partner have the same strain of herpes, there is no risk in engaging in vaginal or oral sex in the third trimester. Your doctor can perform a blood test if you don't know your herpes status. Having anal sex then vaginal sex can transfer harmful bacteria to the vaginal canal. This bacteria can cause vaginal and uterine infections in rare cases. Table anal sex until after birth. Many pregnant mothers also have hemorrhoids during pregnancy, which can make anal sex painful.
Consult your doctor if your pregnancy is high-risk. Use condoms if you're not in a monogamous relationship. Refrain from lying flat on your back after the first trimester. Avoid blowing air into the vagina. Don't have sex in the third trimester if your partner has herpes. Refrain from engaging in anal sex before vaginal sex.