{"id":102564,"date":"2021-06-03T17:36:18","date_gmt":"2021-06-03T15:36:18","guid":{"rendered":"https:\/\/www.ivi.uk\/?p=102564"},"modified":"2022-04-12T17:37:25","modified_gmt":"2022-04-12T15:37:25","slug":"what-are-ovarian-follicles","status":"publish","type":"post","link":"https:\/\/www.ivi.uk\/blog\/what-are-ovarian-follicles\/","title":{"rendered":"What are ovarian follicles?"},"content":{"rendered":"

Ovarian follicles<\/strong> play an essential role in a woman’s fertility \u2013 both in getting pregnant and during the early stages of pregnancy. If you\u2019re hoping to have a baby, it\u2019s useful to have an understanding of how these follicles work.\u00a0<\/p>\n

In this article, we’ll discuss what ovarian follicles are, how they’re measured, why they’re crucial to assisted reproduction treatment, and how they factor into the chances of having a successful pregnancy.<\/span><\/span><\/p>\n

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What are ovarian follicles?<\/span><\/span><\/strong><\/span><\/h3>\n

An ovarian follicle is a fluid-filled sac in which an egg grows. <\/span><\/span><\/span>Once an egg reaches maturity, it is released from the follicle. <\/span><\/span><\/span>This is what we know as <\/span><\/span><\/span><\/span>ovulation<\/span><\/span><\/span><\/span><\/strong> . <\/span><\/span><\/span>While most people have a good grasp of what ovulation involves, fewer may understand exactly what ovarian follicles are and their role in the process of getting pregnant.<\/span><\/span><\/span><\/span><\/p>\n

\"What<\/p>\n

How do ovarian follicles develop?<\/span><\/span><\/span><\/h3>\n

During each monthly menstrual cycle, women develop several follicles, <\/span><\/span><\/span><\/span>measuring around 0.025 mm<\/span><\/span><\/span><\/span><\/a> to begin with. <\/span><\/span><\/span>Most women can expect to develop five or six follicles. <\/span><\/span><\/span>Over the course of the cycle, the follicles respond to various hormones and signals that trigger their growth. <\/span><\/span><\/span>In particular, the <\/span><\/span><\/span><\/span>follicle stimulating hormone (FSH)<\/span><\/span><\/span><\/span><\/strong> , released by the pituitary gland, which causes the follicles to mature. <\/span><\/span><\/span><\/span><\/p>\n

FSH has another important role: it also slows down the growth of the smaller follicles to allow stronger ones to thrive. <\/span><\/span><\/span>As the ovarian follicles grow, they begin releasing higher amounts of <\/span><\/span><\/span><\/span>estrogen<\/span><\/span><\/span><\/span><\/strong> . <\/span><\/span><\/span>As the level of <\/span><\/span><\/span><\/span>estrogen<\/span><\/span><\/span><\/span><\/strong>increases, it signals to the pituitary gland to reduce FSH production. <\/span><\/span><\/span>As FSH levels decline, the smaller follicles begin to stop growing as quickly (or at all), allowing the bigger, stronger follicles to carry on developing.<\/span><\/span><\/span><\/span><\/p>\n

As the smaller follicles disintegrate, they leave behind one or two strong follicles. <\/span><\/span><\/span>When fully grown, these follicles release large amounts of estrogen. <\/span><\/span><\/span>This encourages the pituitary gland to start releasing <\/span><\/span><\/span><\/span>luteinising hormone (LH)<\/span><\/span><\/span><\/span><\/strong> . <\/span><\/span><\/span>This hormone is responsible for the follicle’s final development, before it bursts open to release the egg. <\/span><\/span><\/span>Although it may seem like there’s a lot going on, you can trust your body knows what it’s doing! <\/span><\/span><\/span>This whole process usually takes around 14 to 16 days, with the release of egg from its follicle marking <\/span><\/span><\/span><\/span>ovulation<\/span><\/span><\/span><\/span><\/strong> .<\/span><\/span><\/span><\/span><\/p>\n

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Lifecycle of an ovarian follicle<\/span><\/span><\/span><\/span><\/strong><\/span><\/h3>\n

Here are the various follicular stages:<\/span><\/span><\/span><\/span><\/p>\n

The lifecycle of an ovarian follicle begins at birth. <\/span><\/span><\/span>Women are born with a finite number of ovarian follicles, each containing a primary oocyte, or egg. <\/span><\/span><\/span>Each follicle has the potential to go through its full lifecycle right through to ovulation, but only around <\/span><\/span><\/span><\/span>one per cent of ovarian follicles will reach a stage to support ovulation<\/span><\/span><\/span><\/span><\/a> . <\/span><\/span><\/span>This means only one per cent of ovarian follicles will release an egg.<\/span><\/span><\/span><\/span><\/p>\n