What is HCG?
Human Chorionic Gonadotrophin Hormone, or HCG, is a pregnancy hormone. HCG can be detected very early in a pregnant woman’s blood or urine. High HCG levels may or may not indicate you are having twins but is a never an absolute indicator that you are. However, higher HCG levels are often a first indicator of having twins.
Home pregnancy tests measure HCG levels to determine if you are likely to be pregnant. While they do not pinpoint specific HCG levels, there are some indicators home pregnancy tests can offer as to whether or not you may be carrying twins. If you have a very early positive home pregnancy test you may be carrying twins. If you are using a less sensitive test and get an instant positive (quickly turns very dark) you may be carrying twins.
Your doctor or health care provider will likely measure HCG levels to a more exact measurement during your first visit to confirm your pregnancy. The following HCG results may mean you’re having twins:
- Twice the average level of HCG hormones present
- HCG levels rapidly increase (about 60% in 48 hours)
- One study claims a woman is more likely to be carrying twins if HCG is 600 higher at 16dpo
- Twins or multiples are common in women with HCG levels 30-50% higher than the average woman carrying a single baby
Normal HCG levels vary widely from person to person and with various types of pregnancies (molar pregnancy) and other conditions, which is why even a blood test performed at the doctor’s office cannot 100% confirm you are having twins.
Other signs you’re having twins or multiples
There are multiple signs and symptoms that point to the potential for carrying twins. Some are scientific and some symptomatic and anecdotal.
Doppler Heartbeat Count
A doppler system uses noninvasive sound waves to amplify fetal heartbeats late into the third trimester. An experienced technician may be able to detect multiple heartbeats during this test if present. This test is not perfect as a “second heartbeat” may actually be one baby’s heartbeat echoing or being heard from a different angle.
Extra Morning Sickness
Some say twins make moms-to-be “twice as sick and three times as tired.” It is statistically proven that mothers of multiples can experience increased morning sickness, but that is not always the case. Moms carrying single babies may also have extra morning sickness, but not necessarily be carrying twins. About half of all women experience some sort of morning sickness whether they are carrying twins or not.
The alpha-fetroprotein (AFP) screening is performed during the second trimester and measures for certain birth defects and markers for twins. You may be having twins if you get an unusually positive or high result.
How to confirm you’re having twins
There are some mothers of twins who say they had suspicions they were carrying twins before any signs or tests were present or performed, while other mothers are shocked to find they are carrying more than one baby. While signs, symptoms and tests may indicate a mother is carrying twins or multiples, many of the same signs and symptoms of twins can be present in all pregnancies and there is only one way to know for sure that you are having twins—via an ultrasound. In fact, it is impossible to know you are carrying twins without one, even if your HCG levels are elevated at one or more points in your pregnancy.
During an ultrasound, which takes photo and video of what is going on in the uterus, the doctor or caregiver will be able to see multiple fetuses or hear multiple heartbeats and confirm whether not not you are having twins.
On very rare occasions, even an ultrasound may not clearly show a twin is present. It is rare for an ultrasound to be performed after 20 weeks and not detect a twin if one is present, but before then the chances are higher. The second baby did not materialize along the way, but was rather hidden in some way in the original images, which are not a comprehensive view of the womb and can obstructed to hide the second twin.
What affects my chances of having twins?
There are a variety of factors than may influence your chances of having twins. Fertility treatments, such as in vitro fertilization (IVF) increases chances of twins and multiples. Since twins result from fertilization of more than one egg at a time, older woman who get pregnant may have a higher chance of having twins if they release more than one egg at a time with age. Family history and genetics also play a large role, especially in twin pregnancies that did not result from a fertility treatment. Certain lifestyles and getting pregnant in specific locations have also been claimed as links to having twins.