<a href="https://en.wikipedia.org/wiki/Biparietal_diameter" class="extiw" title="en:Biparietal diameter">Biparietal diameter</a> of a fetus by <a href="https://en.wikipedia.org/wiki/gestational_age" class="extiw" title="en:gestational age">gestational age</a>, with blue line representing the <a href="https://en.wikipedia.org/wiki/mean" class="extiw" title="en:mean">mean</a> and the green area representing the 90% <a href="https://en.wikipedia.org/wiki/prediction_interval" class="extiw" title="en:prediction interval">prediction interval</a>. 
<p>Reference:
</p>
<ul><li><cite style="font-style:normal"> (Jan 1994). "Fetal biometry at 14-40 weeks' gestation.". <i>Ultrasound Obstet Gynecol</i> <b>4</b> (1): 34-48. <a href="https://en.wikipedia.org/wiki/Digital_object_identifier" class="extiw" title="w:Digital object identifier">DOI</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1046/j.1469-0705.1994.04010034.x">10.1046/j.1469-0705.1994.04010034.x</a>.</cite></li></ul>
In addition to data taken from this study, the diagram is extrapolated from 0 to 14 weeks of gestational age by the rationale that it is 0 by fertilization at 2 weeks of gestational age.
<p><a href="https://en.wikipedia.org/wiki/User:Mikael_H%C3%A4ggstr%C3%B6m" class="extiw" title="en:User:Mikael Häggström">Mikael Häggström</a>.
</p><p>When using this image in external works, it may be cited as:
</p>
<ul><li><cite style="font-style:normal">Häggström, Mikael (2014). "<a class="external text" href="https://en.wikiversity.org/wiki/WikiJournal_of_Medicine/Medical_gallery_of_Mikael_H%C3%A4ggstr%C3%B6m_2014">Medical gallery of Mikael Häggström 2014</a>". <i>WikiJournal of Medicine</i> <b>1</b> (2). <a href="https://en.wikipedia.org/wiki/Digital_object_identifier" class="extiw" title="w:Digital object identifier">DOI</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.15347/wjm/2014.008">10.15347/wjm/2014.008</a>. <a href="https://en.wikipedia.org/wiki/International_Standard_Serial_Number" class="extiw" title="en:International Standard Serial Number">ISSN</a> <a rel="nofollow" class="external text" href="https://www.worldcat.org/issn/2002-4436">2002-4436</a>.</cite> <a rel="nofollow" class="external text" href="https://creativecommons.org/publicdomain/zero/1.0/deed.en">Public Domain</a>.</li></ul><p>or
</p>
<ul><li><i>By Mikael Häggström, used with permission.</i></li></ul>
<span class="int-own-work" lang="en">Own work</span>