At 5 weeks pregnant, signs of twins are usually intensified singleton symptoms like extreme fatigue, intense nausea/vomiting, very tender breasts, frequent urination, and stronger food cravings due to higher hCG levels, but an ultrasound is the only definitive way to know for sure; symptoms often mirror a strong singleton pregnancy but are amplified, especially with fertility treatments or family history.
Are there early signs of twins? You won't know for sure if you're carrying twins until you have an ultrasound, but there may be a few early signs. Some telltale early signs that you may be carrying twins include more severe morning sickness, extreme breast tenderness, or gaining weight more quickly.
Understanding Multiple Pregnancies
In most cases, twins can be detected as soon as 6 weeks of gestation in an early pregnancy scan.
Fundal height is greater than gestational age. The baby bump is measuring larger than expected. Gaining weight quickly. Having high levels of hCG, a pregnancy hormone, or alpha-fetoprotein (AFP), a protein made by the fetus's liver. Hearing more than one heartbeat on a fetal Doppler.
In a twin pregnancy, there are elevated levels of hCG, making it possible to have a very early positive result. However, home pregnancy tests won't confirm if twins are present, only the presence of hCG. It takes around 2 weeks after conception for hCG to be detected in a hCG pregnancy test.
You're very hungry or you gain weight quickly in the first trimester. You feel movement in different parts of your belly at the same time. You have severe morning sickness. Morning sickness is nausea (feeling sick to your stomach) and vomiting that happens in the first few months of pregnancy.
Nausea and/or vomiting.
Many women experience pregnancy nausea, which typically starts between 4 and 8 weeks of pregnancy. Nausea is sometimes, not always, accompanied by vomiting.
Early pregnancy symptoms may feel stronger or start sooner when carrying twins. You might notice: More intense nausea (morning sickness) Extreme tiredness.
Pregnant women should also try to avoid all marinated foods, pickled goods, processed foods, foods that are high in monosodium glutamate, as well as caffeinated drinks like tea, coffee and carbonated drinks as these all contain substances which could have adverse effects on the health of your unborn child.
One study shows a range of 217-8,245 mIU/mL at 5 weeks. So it's more helpful to track the rise in hCG over time with blood tests if you're concerned. Around week 6 or 7, hCG rates begin slowing. This is true for both singleton and twin pregnancies.
But with twins, you may also have earlier and more intense symptoms from pregnancy, like morning sickness, swelling, heartburn, leg cramps, bladder discomfort, and sleep problems.
There's no perfect time to share your pregnancy—do what feels right for you. Many wait until after the first trimester. Miscarriage risk drops after 13 weeks, but it's also OK to tell trusted loved ones earlier for support.
You might suspect you're having twins if your pregnancy symptoms feel extra intense — think: stronger morning sickness, major fatigue, and quicker weight gain — but you won't know for sure until that first ultrasound, usually between 6 and 9 weeks.
5 to 8 Weeks
This is important considering all the growth and development your babies are experiencing during this time: Your twins start forming brains and spinal cords. Around 6 weeks, your babies' spinal cords and brains will develop from the neural tubes. Little arms and legs start to form.
Week 4 - implantation
In weeks 4 to 5 of early pregnancy, the blastocyst grows and develops within the lining of the womb. The outer cells reach out and form links with your blood supply. After some time, they will form the placenta (afterbirth). The inner group of cells will develop into the embryo.
The "worst" week of the first trimester often centers around weeks 8 or 9, when pregnancy hormones (especially hCG) peak, making symptoms like severe fatigue and intense morning sickness (nausea/vomiting) most pronounced, though this varies, with fatigue sometimes hitting earlier (weeks 6-8) and symptoms generally easing as you enter the second trimester around weeks 12-14.
Toxoplasmosis (tok-so-plaz-MOE-sis) is an infection with a parasite called Toxoplasma gondii. People often get the infection from eating undercooked meat. You can also get it from contact with cat feces. The parasite can pass to a baby during pregnancy.
The Early Signs of a Twin Pregnancy
Early pregnancy symptoms (at 5 weeks)
The symptoms of twin pregnancies are similar to a singleton pregnancy, but there are some notable differences. You may experience more nausea or fatigue and notice some additional symptoms that singleton pregnancies don't typically present.
Overall, 70% to 80% of women can experience some amount of nausea and vomiting with pregnancies, and up to 2% reportedly experience hyperemesis gravidarum, a form of severe morning sickness. At the same time, some moms of twins and triplets say they have no morning sickness.
Having twins is a very different experience from a singleton pregnancy: Your symptoms may be more intense, you'll need to schedule extra appointments and testing, your calorie intake and weight gain requirements are higher, and there are more risks of certain pregnancy complications.