2. Basis of Presentation and significant accounting policies

Unaudited interim financial data

The accompanying unaudited condensed consolidated balance sheet as of March 31, 2014, the statements of operations and comprehensive loss for the three months ended March 31, 2014 and 2013, and the statements of cash flows for the three months ended March 31, 2014 and 2013, and the related interim information contained within the notes to the financial statements, have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission for interim financial information. Accordingly, they do not include all of the information and the notes required by U.S. generally accepted accounting principles for complete financial statements. In the opinion of management, the unaudited interim financial statements reflect all adjustments, consisting of normal and recurring adjustments, necessary for the fair presentation of our financial position at March 31, 2014, results of our operations for the three months ended March 31, 2014 and 2013 and our cash flows for the three months ended March 31, 2014 and 2013. The results for the three months ended March 31, 2014 are not necessarily indicative of future results.

Principles of consolidation

The condensed consolidated financial statements include the accounts of OvaScience and the accounts of our wholly-owned subsidiary, OvaScience Securities Corporation. All intercompany transactions have been eliminated in consolidation.

Use of estimates

These condensed consolidated financial statements are presented in conformity with U.S. generally accepted accounting principles which require management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from such estimates.

Summary of significant accounting policies

Our significant accounting policies are described in Note 2, “Summary of Significant Accounting Policies,” in the 2013 Annual Report on Form 10-K.

Net loss per share

Basic and diluted net loss per common share is calculated by dividing net loss applicable to common stockholders by the weighted average number of common shares outstanding during the period. Potentially dilutive shares, including preferred stock, outstanding stock options and unvested restricted stock, are only included in the calculation of diluted net loss per share when their effect is dilutive.

The amounts in the table below were excluded from the calculation of diluted net loss per share, prior to the use of the treasury stock method, due to their anti-dilutive effect (in thousands):

			Period
			from April 5,
			2011
	Three Months Ended		(inception) to
	March 31,		March 31,
	2014	2013	2014
Outstanding stock options and restricted stock units	2,225	2,664	2,225
Unvested founders’ stock	823	1,645	823
Total	3,048	4,309	3,048