Reaching Viability Week: Important Facts Every Parent Should Know

Pregnancy is a wonderful experience filled with excitement, hope, and maybe a little anxiety. For many parents and intended parents, one of the biggest markers is viability week: the week of pregnancy when a baby has a reasonable chance of surviving out of the womb with medical care. Knowing about pregnancy viability by week is reassuring, and they are helpful for informed decision-making, especially for those venturing through the surrogacy process.

Whether you are an expectant parent, considering surrogacy, or currently working with the best surrogacy agency, knowing the facts about viability by week can help make for a smoother transition and for a low-stress experience.

What Does Viability Week Mean?

Viability week is the week in pregnancy when a fetus is likely able to survive outside of the uterus (with medical support). Although medical advances are constantly improving, the generally accepted week of viability is around 24 weeks. Baby's delivered before this time have exponentially higher risks and lower survival rates.

It's important to know viability is not to be interpreted as a week in time, but rather a multitude of factors--fetal developmental self-evidently, lung maturity, access to advanced neonatal care, and health of the pregnancy.

Pregnancy Viability by Week: Key Milestones

Every week of pregnancy is a step forward for the baby’s development. Let’s break down pregnancy viability by week to better understand the journey.

Weeks 20–22: Limited Viability

At this stage, a baby’s organs, particularly the lungs, are still underdeveloped.

Survival outside of the mother, even with an intensive care plan, is exceedingly rare.

The focus is on managing the pregnancy appropriately to avoid complications.

Week 23: Edge of Viability

Some hospitals may try resuscitation attempts if a baby arrives at 23 weeks' gestation. Even so, survival rates are still very low (10-30%).

There is some risk of long-term health complications.

Week 24: Generally Accepted Viability Week

This is considered the generally accepted viability week.

If babies are born at 24 weeks' gestation, their chance of survival is typically greater, often around 50-60% with advanced care in a neonatal unit.

Although survival rates are better, there is still a risk of long-term complications.

Weeks 25-27: Improving Survival Rates

As you progress towards week 27, survival rates progressively improve and will involve better health "outcomes" for babies, especially as gestation progresses.

By week 27, particularly in well-equipped hospitals, survival rates may reach as high as 90%.

Weeks 28 and beyond: Surviving Chances

Most babies will survive if born after week 28, and the chances of survival with no long-term issues are strong, but they may still require care in the NICU.

Why Viability Week Matters for Surrogacy

For intended parents going through the surrogacy process, understanding viability week is crucial. Surrogacy can be emotional and sometimes costly, so reaching this milestone helps put minds at ease.

Most intended parents experience an overwhelming sense of relief after they potentially reach viability at 24 weeks. That relief is definitely amplified when using experienced providers that offer surrogacy services because they help monitor and support all aspects of a successful pregnancy.

Factors that Might Affect Viability

The general milestone for viability is around 24 weeks. However, there are various factors that could influence the exact time a baby could survive outside the womb:

Access to Neonatal Intensive Care – Hospitals have a Level 3 or 4 NICU that can support babies born extremely early.

Fetal Development – The maturity of tissue and organ systems and function (the lungs, and brain, especially) all play a major part.

Pregnancy health – The presence of complications during pregnancy, such as preeclampsia or gestational diabetes, or an infection postpartum can affect the outcomes of delivery.

Multiple Pregnancies – Delivering twins or triplets has the potential to deliver much earlier, and therefore may affect viability.

Maternal Health – The direct factors that influence the baby's outcomes will include the health, nutrition, and quality of prenatal care provided to the mother.

Emotional Impact of Reaching Viability Week