IVF Twins: Chances & Risks

Are you considering IVF and wondering about the possibility of having twins? While some couples dream of twins, it's crucial to understand the chances and potential risks involved. In Chennai, as across the world, fertility specialists like myself prioritize your health and the well-being of your future children. This guide explains the likelihood of IVF twins, the associated risks, and why single embryo transfer (SET) is often the safest approach.

What Is IVF and How Does It Work

In Vitro Fertilization (IVF) is a type of assisted reproductive technology (ART) used to help couples struggling with infertility. The procedure involves stimulating the ovaries to produce multiple eggs, retrieving these eggs from the ovaries, and fertilizing them with sperm in a laboratory. The resulting embryos are then monitored for development. One or more of these embryos are transferred into the woman's uterus, with the hope that it will implant and result in a pregnancy.

In a natural conception, one egg is released, and if fertilized, usually results in a single baby. However, during IVF, multiple eggs are matured and fertilised. Historically, to increase the chances of pregnancy, multiple embryos were often transferred. This practice significantly increased the likelihood of a multiple pregnancy, including twins or even higher-order multiples. Today, with advancements in IVF techniques and embryo selection, the focus has shifted towards transferring fewer embryos, often just one, to minimize risks while maintaining good success rates.

The IVF process consists of several key steps:

1. Ovarian Stimulation: Medications are used to stimulate the ovaries to produce multiple eggs.
2. Egg Retrieval: The eggs are retrieved from the ovaries using a minimally invasive procedure.
3. Fertilization: The eggs are fertilized with sperm in a laboratory dish (conventional insemination) or by injecting a single sperm into each egg (ICSI).
4. Embryo Culture: The fertilized eggs, now embryos, are cultured in the laboratory for several days.
5. Embryo Transfer: One or more embryos are transferred into the woman's uterus.
6. Pregnancy Test: About two weeks after the embryo transfer, a pregnancy test is performed to determine if the procedure was successful.

Who Needs IVF

IVF is a treatment option for a wide range of infertility issues affecting both men and women. Some common reasons why couples in Chennai seek IVF include:

• Female Infertility:
  • Ovulatory Disorders: Problems with ovulation, such as polycystic ovary syndrome (PCOS), can prevent natural conception.
  • Fallopian Tube Damage or Blockage: Blocked fallopian tubes prevent the egg and sperm from meeting.
  • Endometriosis: This condition can affect the function of the ovaries, uterus, and fallopian tubes.
  • Uterine Fibroids: These noncancerous growths in the uterus can interfere with implantation.
  • Premature Ovarian Failure: Early loss of ovarian function can lead to infertility.
• Male Infertility:
  • Low Sperm Count: A low number of sperm can make it difficult to fertilize an egg.
  • Poor Sperm Motility: Sperm that don't swim properly may not be able to reach the egg.
  • Abnormal Sperm Morphology: Sperm with an abnormal shape may have difficulty fertilizing an egg.
• Unexplained Infertility: In some cases, the cause of infertility cannot be identified.
• Genetic Disorders: Couples at risk of passing on a genetic disorder may use IVF with preimplantation genetic testing (PGT) to select embryos that are not affected by the disorder.
• Age-Related Infertility: As women age, their fertility declines, and IVF can help overcome some of these challenges. In my clinical experience, women over 35 often benefit significantly from IVF, especially when combined with advanced techniques like ICSI and preimplantation genetic testing.

Chances of Twins with IVF

The chances of having twins with IVF are higher compared to natural conception, primarily due to the practice of transferring multiple embryos. However, with the growing emphasis on single embryo transfer (SET), the incidence of IVF twins is decreasing. Here's a breakdown of the factors influencing the chances of twins:

• Number of Embryos Transferred: Transferring two embryos significantly increases the likelihood of a twin pregnancy compared to transferring a single embryo.
• Age of the Woman: Younger women generally have higher implantation rates, so transferring multiple embryos in younger women carries a greater risk of twins. For women under 35, transferring one or two good-quality (grade I) embryos on day 3 after fertilisation increases the probability of a twin pregnancy.
• Embryo Quality: High-quality embryos have a better chance of implanting, so transferring multiple high-quality embryos increases the risk of twins.
• Clinic Practices: Clinics that routinely transfer multiple embryos will have higher rates of twin pregnancies.
• Patient Preference: Some couples may specifically request multiple embryo transfer in the hope of having twins, although this is generally discouraged due to the associated risks.

According to a meta-analysis, the incidence of monozygotic (identical) twins after assisted conception is about 0.9%, which is 2.25 times higher than in natural conceptions (0.4%). Blastocyst transfer and intracytoplasmic sperm injection (ICSI) are associated with a higher risk of monozygotic twins.

Risks and Side Effects of Twin Pregnancy After IVF

While the idea of having twins may be appealing to some, it's crucial to understand the increased risks associated with twin pregnancies, especially those conceived through IVF. These risks affect both the mother and the babies:

• Preterm Birth: Twin pregnancies are much more likely to result in preterm birth (before 37 weeks of gestation). Preterm babies are at higher risk of health problems, including respiratory distress syndrome, feeding difficulties, and developmental delays. IVF twins have a slightly increased risk of preterm birth compared to naturally conceived twins. One meta-analysis showed a 23% increased risk of preterm birth in IVF twins.
• Low Birth Weight: Twins are often born with lower birth weights than singletons, increasing the risk of health complications. A meta-analysis showed a 14% increased risk of low birth weight in IVF twins.
• Gestational Diabetes: Women carrying twins are at higher risk of developing gestational diabetes, which can lead to complications during pregnancy and delivery.
• Preeclampsia: This condition, characterized by high blood pressure and protein in the urine, is more common in twin pregnancies and can be dangerous for both mother and babies.
• Cesarean Delivery: Twin pregnancies are more likely to require Cesarean delivery due to complications such as malpresentation (one or both babies not in the head-down position). IVF twins have an increased rate of Cesarean delivery.
• Vanishing Twin Syndrome: In some cases, one of the twins may disappear early in the pregnancy, a phenomenon known as vanishing twin syndrome.
• Twin-to-Twin Transfusion Syndrome (TTTS): This complication can occur in identical twin pregnancies where the twins share a placenta. TTTS can lead to unequal blood flow between the twins, resulting in serious health problems.
• Increased Maternal Morbidity: Twin pregnancies increase the risk of maternal complications such as postpartum hemorrhage (excessive bleeding after delivery) and thromboembolism (blood clots).

Single vs Double Embryo Transfer

Given the increased risks associated with twin pregnancies, fertility specialists increasingly recommend single embryo transfer (SET), especially for younger women with good-quality embryos. SET involves transferring only one embryo to the uterus, eliminating the possibility of a twin pregnancy.

Advantages of SET:

• Reduced Risk of Multiple Pregnancy: SET eliminates the risk of twins and higher-order multiples, thereby reducing the risk of preterm birth, low birth weight, and other complications.
• Improved Maternal Health: By avoiding twin pregnancies, SET reduces the risk of gestational diabetes, preeclampsia, and other maternal health problems.
• Comparable Success Rates: With advancements in IVF techniques and embryo selection, SET can achieve comparable success rates to multiple embryo transfer in many cases.
• Reduced Healthcare Costs: Avoiding the complications associated with twin pregnancies can reduce overall healthcare costs.

Disadvantages of Multiple Embryo Transfer:

• Increased Risk of Multiple Pregnancy: Multiple embryo transfer significantly increases the risk of twins and higher-order multiples.
• Higher Risk of Complications: Twin pregnancies are associated with a higher risk of preterm birth, low birth weight, gestational diabetes, preeclampsia, and other complications.
• Increased Healthcare Costs: Managing twin pregnancies and the associated complications can increase healthcare costs.

ASRM, ESHRE, and NICE guidelines emphasize elective single embryo transfer (eSET) to reduce multiple pregnancy rates. ASRM recommends eSET, especially in favorable prognosis patients. ESHRE recommends eSET should be performed if a twin pregnancy is contraindicated or if a couple wishes to avoid a twin pregnancy at any cost. In my practice across Chennai, I strongly advocate for SET, especially in younger patients with good prognosis, due to the significantly reduced risks and comparable success rates. Single embryo transfer is a core part of our IVF treatment in Chennai, supported by careful embryo grading to choose the single best embryo.

IVF Cost in Chennai

The cost of IVF in Chennai can vary depending on several factors, including the clinic, the medications used, and the specific procedures required. Here's a general overview of the costs involved:

• Initial Consultation: ₹500 - ₹1,500
• Diagnostic Tests: ₹5,000 - ₹15,000 (including blood tests, ultrasound, and semen analysis)
• Medications: ₹50,000 - ₹1,00,000 (for ovarian stimulation)
• Egg Retrieval: ₹20,000 - ₹30,000
• Fertilization (IVF or ICSI): ₹15,000 - ₹25,000
• Embryo Transfer: ₹10,000 - ₹20,000
• Freezing and Storage: ₹15,000 - ₹25,000 per year

Therefore, the total cost of a single IVF cycle in Chennai typically ranges from ₹1,50,000 to ₹2,50,000. Additional procedures, such as preimplantation genetic testing (PGT) or ICSI, will add to the overall cost.

Disclaimer: These are approximate ranges for Chennai in 2026 — your actual cost will depend on your specific diagnosis and treatment plan. A detailed estimate is provided after your initial consultation.

What to Expect After IVF

After the embryo transfer, it's essential to follow your fertility specialist's instructions carefully. Here are some general guidelines:

• Rest: Take it easy for the first few days after the transfer. Avoid strenuous activities and heavy lifting.
• Medications: Continue taking any prescribed medications, such as progesterone, as directed by your doctor.
• Diet: Maintain a healthy diet and stay hydrated.
• Avoid Hot Tubs and Saunas: High temperatures can be harmful to the developing embryo.
• Pregnancy Test: A pregnancy test is typically performed about two weeks after the embryo transfer.
• Early Pregnancy Care: If the pregnancy test is positive, you'll need to schedule regular prenatal appointments with your obstetrician.

It is important to note that some patients may experience loose motions after embryo transfer, which can be concerning, but is often manageable.

When to Seek Professional Help

If you're struggling to conceive, or if you have any concerns about your fertility, it's essential to seek professional help from a qualified fertility specialist. A fertility specialist can evaluate your individual situation, identify any underlying causes of infertility, and recommend the most appropriate treatment options. For personalised guidance, book a consultation with Dr. Rukkayal Fathima.